My 340 getting 6 mpg

Modified 340, 3.73 gears, 750 double pumper; what were you expecting?
I get about 10 MPG in town with 3.55s, a 340 that is at about 375HP, headers and vac secondary carb. I have gotten 15 MPG or so on the highway at 60 MPH. Any faster and the gas milage drops. I am fine with my MPG. I did not build my car for gas mileage. Anybody who says they are getting great gas mileage with a 340 has not built it for any level of performance. In my opinion, you can have performance or gas mileage.